Forget the ro water, it's not needed for a ray, im in Utah we have hard water, consistently the same water conditions in the tank is best rather then changing and.fighting what the water already is. as long as you have the Bio filtration available and mechanical and do lots of water changes and feed your ray lots of good food you will do great. You can pm me if you have any questions. What size are you getting your ray at? Find out what food its eating now, also make sure you see it eat at the store, ask for it to be fed. Plan to upgrade your tank, what size tank you putting it in? Search local places for the cheapest market shrimp to buy.
Sent from my DROIDX using MonsterAquariaNetwork App